Amanda Staveley has given Mike Ashley a two-week deadline to accept an offer for Newcastle United, according to a report.
The Times claim that Staveley is keen for a takeover to be completed well before the end of the January transfer window.
Middle East-based financier Staveley's PCP Capital Partners, it reports, has made an offer of a one-off payment of £250million.
Owner Ashley, however, is understood to value United, bought a decade ago for £134million, at closer to £400million.
The report adds that there is "little prospect of Staveley increasing her bid significantly".
Newcastle are 15th in the Premier League and Staveley wants a relegation clause in the deal which would see her get a rebate in the event of the club dropping out of the Premier League this season.